硫掺杂钛酸(盐)纳米管的表征与可见光光催化活性

Characterization and Visible Light-Responsive Photocatalytic Performance of Sulfur-Doped Titanate Nanotubes

以二硫化钛为钛源和硫源,通过与NaOH水热反应成功制备了硫掺杂钛酸(盐)纳米管。采用X射线衍射、高分辨透射电子显微镜、扫描电子显微镜、扩展X射线吸收精细结构(EXAFS)和X光微区分析等手段对所制备的硫掺杂钛酸(盐)纳米管的结构、形貌、硫掺杂状态和掺杂量进行了表征,并以可见光光催化氧化乙醇反应为探针,采用原位气相色谱技术研究了硫掺杂钛酸纳米管的可见光光催化活性;结果表明,S原子以S2-形式取代了钛酸纳米管骨架中O原子的位置,有效实现了硫掺杂;硫掺杂钛酸(盐)纳米管壁厚平均尺寸为2.9 nm,管径平均尺寸为9.7 nm。可见光光催化氧化乙醇反应结果表明,掺硫钛酸纳米管在极低的掺硫量条件下,表现出比未掺杂的二氧化钛纳米管具有更高的可见光光催化活性。

The sulfur-doped titanate and sodium titanate nanotubes （STNTs） were prepared by hydrothermal reaction of sodium hydroxide （NaOH） with titanium disulphide （TiS2 ）, which was used as sulfur source and titanium source for the first time. The structure, morphology, sulfur-doped valence state and doped amount of the as-obtained STNTs were characterized by X-ray diffraction （XRD）, high resolution transmission electron microscopy（ HRTEM ）, scanning electron microscope （SEM）, extended X-ray absorption fine structure （EXAFS）, and energy dispersive X-ray（EDS）. The photo-oxidation reaction of ethanol under visible light was used to probe the reaction, and the visible light-responsive photocatalytic activity of sulfur-doped titanate nanotube was investigated by means of in-situ gas chromatography （GC）. The results indicated that S atoms were introduced into the lattice of titanate nanotubes as S2- anions. The average size of wall thickness and diameter of STNTs were 2. 9 nm and 9. 7 nm, respectively. The visible light-responsive photocatalytic oxidation results indicated that the SNTTs with very low amount of doped sulfur showed higher photocatalytic activity than undoped TiO2 nanotubes.